Question

The length of the rectangle is twice its breadth. If half of its perimeter is 18 cm, what will be the area(in sq. cm) of the green triangle?

Answer 1

Half of the perimeter of the rectangle = Length + Breadth
Length + Breadth = 18 cm
It is given that, length = 2 × breadth.
So, 3 × breadth = 18
Therefore, breadth = 6 cm
Length = 6 × 2 = 12 cm
So, the area of the rectangle = 12 × 6
= 72 sq. cm
As we know that the area of the triangle is half of the area of the rectangle.
So, area of the green triangle = 72 ÷ 2
= 36 sq. cm